问题补充:
I wondered what difficulty he had the plan?
A. to carry out
B. carrying out
C. carried out
D. with carrying out
答案:
A. to carry out
(答案→)B. carrying out
C. carried out
D. with carrying out
解析:本题考查非谓语动词。此处he had是定语从句,引导词代替difficulty做had的宾语,省略了。补充完整是he had that(difficulty)(in)carrying out…。